chore: Use embedded graphviz instead of the dot command

cmd/server/demo.go

@@ -7,12 +7,10 @@ import (
 	"errors"
 	"fmt"
 	"html/template"
-	"io"
 	"net/http"
-	"os/exec"
 	"strings"
-	"time"
 
+	"github.com/goccy/go-graphviz"
 	"github.com/ikawaha/kagome/v2/tokenizer"
 )
 
@@ -27,11 +25,6 @@ var (
 	demoT    = template.Must(template.New("demo").Parse(demoHTML))
 )
 
-const (
-	graphvizCmd = "dot"
-	cmdTimeout  = 25 * time.Second
-)
-
 // TokenizeDemoHandler represents the tokenizer demo server struct.
 type TokenizeDemoHandler struct {
 	tokenizer *tokenizer.Tokenizer
@@ -80,31 +73,21 @@ func toRecords(tokens []tokenizer.Token) []record {
 }
 
 func (h *TokenizeDemoHandler) analyzeGraph(ctx context.Context, sen string, mode tokenizer.TokenizeMode) (records []record, svg string, err error) {
-	if _, err := exec.LookPath(graphvizCmd); err != nil {
-		return nil, "", errors.New("circo/graphviz is not installed in your $PATH")
-	}
-	ctx, cancel := context.WithTimeout(ctx, cmdTimeout)
-	defer cancel()
 	var b bytes.Buffer
-	cmd := exec.CommandContext(ctx, graphvizCmd, "-Tsvg")
-	r0, w0 := io.Pipe()
-	cmd.Stdin = r0
-	cmd.Stdout = &b
-	cmd.Stderr = Stderr
-	if err := cmd.Start(); err != nil {
-		return nil, "", fmt.Errorf("process done with error, %w", err)
+	tokens := h.tokenizer.AnalyzeGraph(&b, sen, mode)
+	graph, err := graphviz.ParseBytes(b.Bytes())
+	if err != nil {
+		return nil, "", err
 	}
-	tokens := h.tokenizer.AnalyzeGraph(w0, sen, mode)
-	if err := w0.Close(); err != nil {
-		return nil, "", fmt.Errorf("pipe close error, %w", err)
+	g, err := graphviz.New(ctx)
+	if err != nil {
+		return nil, "", err
 	}
-	if err := cmd.Wait(); err != nil {
-		return nil, "", fmt.Errorf("process done with error, %w", err)
+	b.Reset()
+	if err := g.Render(ctx, graph, graphviz.SVG, &b); err != nil {
+		return nil, "", fmt.Errorf("render error: %w", err)
 	}
 	svg = b.String()
-	if pos := strings.Index(svg, "<svg"); pos > 0 {
-		svg = svg[pos:]
-	}
 	records = toRecords(tokens)
 	return records, svg, nil
 }

cmd/server/demo_test.go

@@ -6,7 +6,6 @@ import (
 	"io"
 	"net/http"
 	"net/http/httptest"
-	"os/exec"
 	"reflect"
 	"strings"
 	"testing"
@@ -60,9 +59,6 @@ func TestTokenizeDemoHandler_ServeHTTP(t *testing.T) {
 	})
 
 	t.Run("w/ lattice", func(t *testing.T) {
-		if _, err := exec.LookPath(graphvizCmd); err != nil {
-			t.Skipf("graphviz command not found, %v", err)
-		}
 		req := httptest.NewRequest(http.MethodPost, `/?s=ねこです&r=Search&lattice=true`, nil)
 		w := httptest.NewRecorder()
 		(&TokenizeDemoHandler{tokenizer: tnz}).ServeHTTP(w, req)
@@ -86,9 +82,6 @@ func TestTokenizeDemoHandler_ServeHTTP(t *testing.T) {
 }
 
 func TestTokenizeDemoHandler_analyzeGraph(t *testing.T) {
-	if _, err := exec.LookPath(graphvizCmd); err != nil {
-		t.Skipf("graphviz command not found, %v", err)
-	}
 	tnz, err := tokenizer.New(loadTestDict(t))
 	if err != nil {
 		t.Fatalf("unexpected error, %v", err)
@@ -116,11 +109,8 @@ func TestTokenizeDemoHandler_analyzeGraph(t *testing.T) {
 	}; !reflect.DeepEqual(got, want) {
 		t.Errorf("got %+v, want %v", got, want)
 	}
-	if !strings.HasPrefix(svg, "<svg width=") {
-		if len(svg) > 50 {
-			svg = svg[:50]
-		}
-		t.Errorf("broken svg, %s", svg)
+	if len(svg) == 0 {
+		t.Errorf("svg is empty")
 	}
 }
 

go.mod

@@ -1,9 +1,20 @@
 module github.com/ikawaha/kagome/v2
 
-go 1.19
+go 1.23.2
 
 require (
+	github.com/goccy/go-graphviz v0.2.4
 	github.com/ikawaha/kagome-dict v1.1.0
 	github.com/ikawaha/kagome-dict/ipa v1.2.0
 	github.com/ikawaha/kagome-dict/uni v1.2.0
 )
+
+require (
+	github.com/disintegration/imaging v1.6.2 // indirect
+	github.com/flopp/go-findfont v0.1.0 // indirect
+	github.com/fogleman/gg v1.3.0 // indirect
+	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 // indirect
+	github.com/tetratelabs/wazero v1.8.1 // indirect
+	golang.org/x/image v0.21.0 // indirect
+	golang.org/x/text v0.19.0 // indirect
+)

go.sum

@@ -1,6 +1,28 @@
+github.com/corona10/goimagehash v1.1.0 h1:teNMX/1e+Wn/AYSbLHX8mj+mF9r60R1kBeqE9MkoYwI=
+github.com/corona10/goimagehash v1.1.0/go.mod h1:VkvE0mLn84L4aF8vCb6mafVajEb6QYMHl2ZJLn0mOGI=
+github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1ei82L+c=
+github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
+github.com/flopp/go-findfont v0.1.0 h1:lPn0BymDUtJo+ZkV01VS3661HL6F4qFlkhcJN55u6mU=
+github.com/flopp/go-findfont v0.1.0/go.mod h1:wKKxRDjD024Rh7VMwoU90i6ikQRCr+JTHB5n4Ejkqvw=
+github.com/fogleman/gg v1.3.0 h1:/7zJX8F6AaYQc57WQCyN9cAIz+4bCJGO9B+dyW29am8=
+github.com/fogleman/gg v1.3.0/go.mod h1:R/bRT+9gY/C5z7JzPU0zXsXHKM4/ayA+zqcVNZzPa1k=
+github.com/goccy/go-graphviz v0.2.4 h1:3ujZoLVp7dT2lxuUPeaZvkFQtHU8E54d/LlDc/idrHQ=
+github.com/goccy/go-graphviz v0.2.4/go.mod h1:hssjl/qbvUXGmloY81BwXt2nqoApKo7DFgDj5dLJGb8=
+github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g=
+github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k=
 github.com/ikawaha/kagome-dict v1.1.0 h1:ePU16KkyonhYLo4YDf/UExmZJBhY/6C946T1SOg1TI4=
 github.com/ikawaha/kagome-dict v1.1.0/go.mod h1:tcbTxQQll5voEBnJqGYt2zJuCouUL6buAOrpSxzo9Fg=
 github.com/ikawaha/kagome-dict/ipa v1.2.0 h1:lgehXOf2USDkBwGPEBD9sbbOBk3WlkhZ2zejPSLjIJA=
 github.com/ikawaha/kagome-dict/ipa v1.2.0/go.mod h1:LRtB3BXipG3Iu4V+KI/E1E7r9GMa79WgAH6IAW4wy6A=
 github.com/ikawaha/kagome-dict/uni v1.2.0 h1:BMv15D69ngwD0Yqc3QiniAYpYAQ+IRDvBGTk/Jqj8dw=
 github.com/ikawaha/kagome-dict/uni v1.2.0/go.mod h1:wHaaFLLTKRJVGzElVED9RiMABZ8GSsaaJ7Tn3wzNon4=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
+github.com/tetratelabs/wazero v1.8.1 h1:NrcgVbWfkWvVc4UtT4LRLDf91PsOzDzefMdwhLfA550=
+github.com/tetratelabs/wazero v1.8.1/go.mod h1:yAI0XTsMBhREkM/YDAK/zNou3GoiAce1P6+rp/wQhjs=
+golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
+golang.org/x/image v0.21.0 h1:c5qV36ajHpdj4Qi0GnE0jUc/yuo33OLFaa0d+crTD5s=
+golang.org/x/image v0.21.0/go.mod h1:vUbsLavqK/W303ZroQQVKQ+Af3Yl6Uz1Ppu5J/cLz78=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.19.0 h1:kTxAhCbGbxhK0IwgSKiMO5awPoDQ0RpfiVYBfK860YM=
+golang.org/x/text v0.19.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=